another theory is that when cersei and jaime were boning in S1 E1 and bran saw them, it wasn't really them- it was the faceless man pretending to be cersei and jaime boning and it was the faceless man who threw bran off the tower. EXCEPT, it wasn't really bran, it was the faceless man pretending to be bran.
daenerys targaryen? yep, the faceless man. her dragons? his dog.
basically the show is about a guy in detroit who has schizophrenia and sees all of these illusions around him and tries to hurt himself